California Code, Water Code - WAT § 26658

Lands sold to the district remaining unredeemed after five years have elapsed from the date of their sale for delinquent district assessments shall be deeded to the district by the county tax collector.  The deed shall be substantially in the form provided for collector's deeds by Section 26276 of the Water Code and shall have the same effect and be recorded in the same manner as irrigation district's collector's deeds under the provisions of Articles 4 and 5 of Chapter 6 of this part.  Land which has been declared to be tax-defaulted remaining unredeemed after five years have elapsed from the date of the tax-default for delinquent district assessments shall become subject to the tax collector's power of sale pursuant to Section 3691 of the Revenue and Taxation Code.